Due to their exposure to the open air because of the cable trays, the wires contained within need a very durable outer covering. The regulations dictate that the cables must either be Type TC (also known as Tray Rated) or must be metal-armored (Type MC). I don't think anyone allows direct burring of cable, or a dangling free run, particularly in an industrial environment. Everyone has their own internal standard as to. Cable Trays: They are suitable for long, straight runs where a large number of wires are present. This is the minimum distance between a primary wall and a specific desk or motor where the. Tray cables (TC, TC-ER, and similar types) are specially designed for use in cable tray systems, which support multiple runs of cable across industrial and commercial buildings. Understanding the types of cable containment systems, including trays, trunks, and conduits, helps engineers and contractors select the best. Common sense says to use conduit to protect wiring in low down areas where it might get knocked or damaged (along skirting boards or the edge of the floor).
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